Non-reciprocal transmission in photonic lattices based on unidirectional coherent perfect absorption

A method for realizing asymmetric (one-way) transmission of discretized light in modulated, linear, and purely passive optical lattices is suggested, which exploits the idea of unidirectional coherent perfect absorption. The system consists of a linear photonic lattice of coupled resonators or waveguides, side coupled to a chain of lossy elements, in which light can avoid the occupation of the dissipative sites when propagating in one way, but not in the opposite one. Non-reciprocity requires modulation of the resonator/waveguide parameters, realizing a dissipative optical Aharonov–Bohm diode with non-reciprocal behavio